CORRECT: 2017/2018 NABTEB GCE BIOLOGY Questions And Answer Expo/Runs « on: Today at 03:42:19 am » 

 Bio OBJ:
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*Theory*_ 1ai)
i. As a colony eg volvox ii. As a filament eg spirogyra iii. As a part of a living organism eg amoeba 1aii) i. It leads to cellular differentiation ii. It leads to internal structural specialisation
iii. It increases adaptation of environment
iv. Complexity leads to efficiency
v. Complexity leads to increase in size
vi. Mutual interdependence between component cell

*DISADVANTAGES *
i. Inability of individual cells to exist on their own
ii. Difficulties in aquisition of oxygen and food materials
iii. It leads to slower rate of diffusion
iv. Slower rate of expulsion of waste products
v. Difficulties in reproduction
vi. Decreases in ability to regenerate

 1bi) -- Virus is on the borderline between living things and non-living things --It possesses characteristics which can be transmitted from one generation to the other
 1bii) -- When a virus is extracted from a living cell and placed in a non living medium, it assumes a crystalline and thus become non living ================= =

 2ai ) -- Carbon iv oxide -- Water and mineral salt -- Sunlight -- Optimum temperature -- Chlorophy ii
 2aii ) Experiment to show that light is necessary for photosynthesis are as follows: *Materials required:* A potted plant, strip of black paper, clips, cupboard. *Method:* The potted plants is first detached by putting it in a dark cupboard for 1-2 days this is to remove all trace of starch formed in the leave after this, the middle of one of the leaves is covered by a strip of black with the ends of clips, the whole plant is then placed in sunlight. After about 3-5 hours, the paper is removed the leaf is then tasted for starch. *OBSERVATION* Only the expose part i.e use top and rotten of the leaf turned blue back with the iodine solution which shows the presence of starch while the area that was covered with black paper will remain colourless, indicating that starch is absent. *CONCLUSION* The experiment shows that light is necessary for photosynthesis.
 2b ) Micro nutrients are: -- Zinc -- Boron -- Copper -- Molybdenum Macro nutrients are: -- Nnitrogen -- Potassium -- Phosphorus -- Magnesium ================= 

3ai) Balance diet is a food containing the correct proportion of all the six classes of nutrients, they are: Carbohydrate Protein Vitamin Fat & Oil Mineral and Water
 3aii) i. It encourages the growth and normal development of the body
ii. It also provide energy required for normal activities iii. Balance diet prevent malnutrition deficiency or diseases

 3b) Method 1: Rub the test substances on a paper or melt it on paper . Result: The paper becomes translucent indicate presence of fat .
 Method 2: To the test substances, add a few drops of osmic acid. Result: Is that there is brownish black coloration indicate the presence of fat.
 Method 3: To about 1cm^3 of milk in a test tube, add a few drops of sudan iv, the Result is that the red colour is obtained showing the presence of fat
 3c ) i. Insects
ii. Birds
iii. Rodents
iv. Monkeys =================

 5a) i. In complex multicellular organisms many cells are situated far away from others hence, substances have to be moved over greater distances.
ii. Use surface area to volume ratio in complex multicellular organism is too small hence the need for an efficient transport system .
iii. A conducting or linking system become necessary to connect isolated groups of cell
iv. Fiffusion alone cannot be used for transportation of materials to isolated cells
v.materials being transported are large in quantities for simple process of diffusion, osmosis, or active transport to accomplish.hence, the need for an efficient transport system in higher organisms. 
6b) Rainguage - Measures the amount of rainfall Anemometer - Measures the speed of wind Light meter - Measures intensity of light